This description relates to managing data queries.
Data can be stored in databases and arranged in various forms such as database tables. A database table can contain a set of data having a common theme or purpose. The arrangement of a database table can be defined by a database scheme, and multiple database tables can have similar or identical arrangements. Further, the contents of a database and its associated database tables can change over time as data is adjusted, appended or deleted. Various techniques can be used to transfer data into and out of a database and to manipulate the data in the database.